Using Vblank, WTF??

[Mairtrus]

Hello, It's me again ;D...
Perhaps this question sounds a little silly, but someone could teach me how to use correctly the interrupters?
Every time I need to make the movement of a character, ship, badnik, etc., always get the same error: "STACK UNDERRUN (START:reset)."
Some generous soul willing to help? Thanks ...

[oompa loompa]

a stack unerrun is when you try to pop more values from the stack, than there actually are. you probably used one too many RETURNs.

i don't remember if there was a way for the 68k processor to detect this. i think the stack address wraps around, without generating an error. so i think basiegaxorz checks for stack underruns

[jlf65]

You could try sticking an odd address on the top of the stack. That would cause an address error when one too many returns is done.